Lepidoptera ( LEP-ih-DOP-tər-ə) or lepidopterans are an order of winged insects which include butterflies and moths. About 180,000 species of the Lepidoptera have been described, representing 8.6% of the total described species of living organisms, making it the second largest insect order (behind Coleoptera) with 126 families and 46 superfamilies, and one of the most widespread and widely recognizable insect orders in the world. Lepidopterans have several distinctive features, especially coloured scales that cover their bodies, large triangular wings, and a proboscis for drinking nectar. Almost all species have membranous wings. Mating and egg-laying are normally near or on host plants for the larvae. Butterflies and moths undergo complete metamorphosis. The larva is called a caterpillar; it has a cylindrical body with a well-developed head, chewing mouthparts, three pairs of legs and up to five pairs of prolegs. As it grows, it changes in appearance, going through a series of stages called instars. Once mature, it develops into a pupa. A few butterflies and many moth species spin a silk casing or cocoon for protection prior to pupating, while others just go underground. A butterfly pupa, called a chrysalis, has a hard skin, usually with no cocoon. In the pupa, metamorphosis occurs, and a sexually mature adult emerges. Lepidopterans first appeared in the fossil record at the Triassic-Jurassic boundary. They have coevolved with flowering plants since the angiosperm boom in the Cretaceous. They have evolved a wide range of wing patterns ranging from camouflaged moths to the vivid displays of butterflies. A person who studies this order is called a lepidopterist. Butterflies and moths are mostly herbivorous as caterpillars and nectar-feeding as adults. They serve as economically useful pollinators; conversely, caterpillars are often pests in agriculture, as they can quickly consume large quantities of leaves. Females often produce up to 600 eggs.
Etymology The term Lepidoptera was used in 1746 by Carl Linnaeus in his Fauna Svecica. The word is derived from Greek λεπίς lepís, gen. λεπίδος lepídos ("scale") and πτερόν ("wing"). The word "butterfly" is from Old English buttorfleoge, possibly from the pale butter color of some species' wings. The word "moth" is from Old English moððe from Common Germanic and German Motte meaning "moth". The word "caterpillar" is from Middle English catirpel, catirpeller, probably an alteration of Old North French catepelose (from Latin cattus, "cat" + pilosus, "hairy").
Distribution and diversity
The Lepidoptera are among the most successful groups of insects. They are found on all continents, except Antarctica, and inhabit all terrestrial habitats ranging from desert to rainforest, from lowland grasslands to mountain plateaus, but almost always associated with higher plants, especially angiosperms (flowering plants). Among the most northern dwelling species of butterflies and moths is the Siberian Apollo (Parnassius arcticus), found in the Arctic Circle in northeastern Yakutia, at an altitude of 1,500 metres (4,900 ft) above sea level. In the Himalayas, Apollo species such as Parnassius epaphus occur up to an altitude of 6,000 metres (20,000 ft). Some species are commensal or parasitic, inhabiting the bodies of organisms rather than the environment. Coprophagous pyralid moths, called sloth moths, such as Bradipodicola hahneli and Cryptoses choloepi, are unusual in that they are exclusively found in the fur of sloths. Two species of Tinea moths feed and breed on the horns of cattle. The larva of Zenodochium coccivorella is an internal parasite of Kermes scale insects. Many species breed in materials such as owl pellets, bat caves, honeycombs or diseased fruit. As of 2007, there were roughly 174,250 lepidopteran species described, with butterflies estimated to comprise around 17,950, and moths making up the rest. The vast majority live in the tropics, but substantial diversity exists on most continents. North America has over 700 species of butterflies and over 11,000 species of moths, while Australia has about 400 species of butterflies and 14,000 species of moths. The diversity in each faunal region has been estimated by John Heppner in 1991 based partly on actual counts from the literature, partly on the card indices in the Natural History Museum (London) and the National Museum of Natural History (Washington), and partly on estimates:
External morphology
Lepidoptera are morphologically distinguished from other orders by the presence of scales on the body and appendages, especially the wings. Butterflies and moths vary in size from microlepidoptera only a few millimeters long, to conspicuous animals with a wingspan greater than 25 centimetres (9.8 in), such as Queen Alexandra's birdwing and Atlas moth.
Head
The head houses sensing organs and mouthparts. Like the adult, the larva has a toughened, or sclerotized head capsule. Here, two compound eyes, and chaetosema, clusters of sensory bristles unique to Lepidoptera, occur, though many taxa have lost one or both of these clusters. The antennae vary widely in form among species and between the sexes. The antennae of butterflies are usually club-shaped, those of the skippers are hooked, while those of moths have segments variously enlarged or branched. The maxillary galeae are modified to form an elongated proboscis. It consists of one to five segments, kept coiled up under the head by small muscles when it is not being used to suck up nectar from flowers. The larvae, called caterpillars, have a toughened head capsule. Caterpillars lack the proboscis and have separate chewing mouthparts. These mouthparts, called mandibles, are used to chew up the plant matter that the larvae eat. The lower jaw, or labium, is weak, but may carry a spinneret, an organ used to create silk. The head is made of large lateral lobes, each having a group of up to six simple eyes.
… excerpt ends here. Continue reading the full article.
